CV

Selected CVEs

• (9.6) CVE-2026-87464: Use after free in WebGL in Google Chrome allowed a remote attacker to execute arbitrary code outside the sandbox via a crafted HTML page (web content to shell)
• (7.1) CVE-2026-63629: CSRF bypass + reflected XSS in error page with CSP bypass
• (9.2) CVE-2026-28431: Pre-auth private message leak for all users in server network in Misskey
• (7.8) CVE-2025-68973: In GnuPG before 2.4.9, armor_filter in g10/armor.c has two increments of an index variable where one is intended, leading to an out-of-bounds write for crafted input.
• (9.8) CVE-2024-56327: age vulnerable to malicious recipients causing arbitrary binary execution
• (6.1) CVE-2023-29345: Microsoft Edge (Chromium-based) Security Feature Bypass Vulnerability

Occupation

• 2022: Artificial Intelligence Engineering Internship at [available upon request], worked with Python, Torch, Jupyter etc. on data science + DNNs
• 2023-2024: Software engineer at [available upon request], worked with Python, Flask, PostgresQL, Svelte and TypeScript on the web frontend and backend; GitLab, Docker and Nix on the CI/CD; and Debian and debootstrap for the required embedded systems; responsible for security of the system
• 2023-2026: Computer science student

CTF

• Player for KITCTF since 2023
• Web main, but after the web fullsolve everything else =)
• Helped my team reach #35 and #42 worldwide in my most active years
• Solo #1 in a GitHub CTF
• Qualified & played at the German Hacking Championship
• Authored various challenges for several competitions contributed by or hosted by KITCTF

Bug Bounty

• Biggest companies I worked with: Microsoft, Meta, Google, GitHub, Twitter
• Some excerpts:
  • Meta: 0click XSS on meta.ai
  • Meta: Wormable stored XSS with CSP bypass escalatable to RCE on Monica.im
  • Meta: Top-level nav to attacker-controlled origin in Monica desktop app leading to IPC bridge hijack escalatable to ATO + RCE
  • Github: Reflected XSS in Codespaces with CSP bypass, leading to RCE, leading to GitHub account compromise
  • GitHub: Exfiltration of sensitive user content (private repo code, issue and pull request bodies, etc.) via CSP Bypass in Copilot Web in issue renderer
  • GitHub: RCE via Copilot in Codespaces leads to persist R/W access to repository via issue body & exeuction mitigation bypass in Code with Agent Mode
  • GitHub: Stored zero-click XSS in GitHub Copilot via unsafe YAML deserialization
  • GitHub: Privilege Escalation in Copilot Coding Agent via pull_request_target workflow in copilot/fix-[n] branch, to persistent backdoor in repos
  • Twitter: Path traversal in the safety notifications relative path combined with card player frames can be used to put an arbitrary iframe source on Twitter.com
  • Microsoft (Edge): Clickjacking protection on permission dialogs not implemented correctly and can be bypassed to make a user grant permissions without consent
  • Google (Chrome): Usage of window movement API can be used to entirely bypass clickjacking protections on permission dialogs and entire windows
  • Monero: Local-only DoS via malicious JSON-RPC payload
  • Bitwarden: bitwarden/mcp-server has command injection, leading to RCE
• Testimonials:
  • You demonstrated a critical vulnerability. Thank you again for your report. We look forward to receiving more reports from you in the future!
  • look forward to more valid and valuable reports from you in the future. :)
  • You've had interesting reports, and I hope to see more from you.
  • Select researcher who discovers the most impactful vulnerabilities in our apps.
  • We really appreciate that you approached us in an ethical manner regarding disclosure of this report, and you've submitted a good number of interesting reports to our program.
  • Kudos to the reporter for the detailed report.

Public Speaking

• NixCon 2024: Pwning the entire Nix ecosystem. CI vulnerabilities and UNIX command-line exploitation leading to read/write access to NixOS infrastructure, researched and presented during the three-day conference.
• MRMCD 2025: When your transport association is too transparent. How a small data leak at a public transport association led to a much larger one, and how we handled the disclosure.
• 39c3 2025: To sign or not to sign: Practical vulnerabilities in GPG & friends. Implementation bugs in GnuPG, Sequoia PGP, age and minisign, including signature spoofing and memory corruption.
• MRMCD 2026: The gpg.fail aftermath. Follow-up on gpg.fail, covering responsible disclosure, unresolved vulnerabilities, new GnuPG bugs and the state of security research.

See my talks page for details.